JP2014215590A - Zoom lens barrel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a zoom lens barrel prevented from being enlarged even when applying a long position sensor.SOLUTION: A lens barrel 10 includes: a fixed barrel 20; a zoom ring 40 arranged outside the fixed barrel 20; a first cam barrel 30 that is integral with the zoom ring 40, and rotates relative to the fixed barrel 20; and first and second straight advance barrels 50, 60 that hold a first lens group A, and are arranged inside the fixed barrel 20. The first and second straight advance barrels 50, 60 can move to an optical axis direction by the rotation of the first cam barrel 30 relative to the fixed barrel 20. A third lens group holding barrel 100 for holding third to fifth lens groups C-E is connected to an attachment part formed behind the first straight advance barrel 50. A part of the straight advance barrel 50 except for the attachment part is arranged closer to an object side than a diaphragm mechanism 101.

Description

  The present invention relates to a zoom lens barrel.

  Conventionally, a fixed cylinder that extends in the axial direction with substantially the same diameter, a rectilinear cylinder that can move in the optical axis direction relative to the fixed cylinder, and a zoom cylinder that rotates in the optical axis direction with respect to the fixed cylinder. A lens barrel having a configuration including a cam barrel that is moved and converted into a driving force is used. For such a lens barrel, for example, a position sensor that optically detects the position of the focus lens as described in Patent Document 1 is used. However, the position sensor that optically detects the position of the focus lens as described above has problems such as deterioration with time and increase in power consumption because the position is electrically detected. Therefore, a long sensor main body extending in the optical axis direction and a protrusion that can move in the optical axis direction with respect to the sensor main body are provided, and the position of the focus lens is adjusted by interlocking the protrusion with the movement of the rectilinear cylinder. A position sensor for detection is also widely used.

JP 2013-24894 A

  On the other hand, in recent years, cameras that do not have a reflex mirror for guiding incident light that has reached the camera body through a lens barrel to an optical viewfinder have been widely sold. A camera that does not include such a reflex mirror can reduce the size and weight of the camera body, and can be used by replacing the lens barrel in the same manner as a single-lens reflex camera. In addition, the zoom lens barrel used in a camera that does not include such a reflex mirror has a long extension amount with a high magnification in the same manner as a zoom lens barrel used in a single-lens reflex camera. Similarly, downsizing is required.

  However, even if a position sensor that detects the position of the focus lens by linking such a protruding portion with the movement of the rectilinear cylinder is applied to a lens barrel of a camera that does not include the reflex mirror as described above, There is a problem that the diameter of the lens barrel is increased in order to secure a space extending in the axial direction.

  The present invention has been made in view of the above problems, and an object thereof is to provide a lens barrel that does not increase in diameter even when a long position sensor is applied. .

  The zoom lens according to the present invention includes at least a first lens group that is movable in the optical axis direction and at least one lens group that is provided closer to the image forming side than the aperture mechanism and is movable in the optical axis direction. A lens barrel, a fixed barrel, a zoom ring disposed outside the fixed barrel, a first cam barrel that is integral with the zoom ring and rotates with respect to the fixed barrel, and a first lens group And a rectilinear cylinder disposed inside the fixed cylinder, and the linear cylinder is movable in the optical axis direction by rotating the first cam cylinder with respect to the fixed cylinder, and is connected to the aperture mechanism. A holding member that holds one or more lens groups that are provided on the image side and that can move in the optical axis direction is connected to an attachment portion formed at the rear of the rectilinear cylinder, and the rectilinear cylinder excluding the attachment portion The portion is provided on the objective side with respect to the diaphragm mechanism.

  According to the present invention, since the portion excluding the mounting portion of the rectilinear cylinder that moves in the optical axis direction with respect to the fixed cylinder is provided in front of the aperture mechanism, a space can be secured in the rear part of the lens barrel. Thereby, a long position detection sensor can be incorporated in the lens barrel without increasing the diameter of the lens barrel.

  In the present invention, preferably, the rectilinear cylinder includes a first rectilinear cylinder arranged inside the fixed cylinder and a second rectilinear cylinder arranged inside the first rectilinear cylinder, and the first rectilinear cylinder The cylinder is movable in the optical axis direction when the first cam cylinder rotates with respect to the fixed cylinder, and the zoom lens barrel is disposed inside the second rectilinear cylinder, together with the first rectilinear cylinder A second cam cylinder that moves in the optical axis direction and rotates in conjunction with the one cam cylinder, and a rectilinear guide cylinder that is disposed inside the second cam cylinder and moves in the optical axis direction together with the first rectilinear cylinder The second rectilinear cylinder moves in the optical axis direction with respect to the first rectilinear cylinder by the rotation of the second cam cylinder with respect to the rectilinear guide cylinder.

  According to the present invention having such a configuration, a long feeding amount can be ensured without increasing the diameter of the lens barrel.

  In the present invention, the fixed cylinder is preferably formed in a shape such that the diameter gradually decreases toward the image forming side in the optical axis direction.

  According to the present invention having such a configuration, a space can be secured in the outer peripheral portion of the lens barrel on the eyepiece side, and a mechanism such as a manual focus mechanism can be incorporated in this portion.

  In the present invention, preferably, the zoom lens barrel includes a zoom interlocking ring that can rotate in conjunction with the first cam cylinder along the inner surface of the fixed cylinder, and a position sensor attached to the rear part of the fixed cylinder. The position sensor includes a sensor body extending in the optical axis direction and a protrusion that is movable in the optical axis direction with respect to the sensor body. The protrusion is connected to the sensor body in conjunction with the rotation of the zoom interlocking ring. Move in the direction of the optical axis.

  According to the present invention, there is provided a lens barrel whose diameter does not increase even when a long position sensor is applied.

FIG. 2 is a cross-sectional view (part 1) of the zoom lens barrel of the present embodiment, taken on planes with different angles around the optical axis in the wide-angle state. FIG. 5 is a cross-sectional view (part 2) of the zoom lens barrel of the present embodiment, taken on planes with different angles around the optical axis in the wide-angle state. FIG. 4 is a cross-sectional view (part 3) of the zoom lens barrel of the present embodiment, taken on planes with different angles around the optical axis in the wide-angle state. It is sectional drawing in the telephoto state in the same plane as FIG. It is a perspective view which shows the 1st rectilinear advance cylinder used for the zoom lens barrel of this embodiment.

Hereinafter, an embodiment of a zoom lens barrel of the present invention will be described in detail with reference to the drawings.
First, the configuration of the lens barrel will be described.
1 to 4 are cross-sectional views showing the zoom lens barrel of the present embodiment. FIGS. 1 to 3 are cross-sectional views in planes at different angles with the optical axis in the wide-angle state as a center. FIG. It is sectional drawing in the telephoto state in the same plane. FIG. 5 is a perspective view showing a first rectilinear barrel used in the zoom lens barrel of the present embodiment.

As shown in FIGS. 1 to 4, the lens barrel 10 of the present embodiment includes a first lens group A, a second lens group B, a third lens group C, a fourth lens group D, a fifth lens group E, and A sixth lens group F is provided. The third lens group C includes a shift lens group Cr that is shifted in a direction orthogonal to the optical axis to prevent camera shake.
The lens barrel 10 includes a mount 11 attached to the camera body, and a fixed barrel 20 integrated with the mount 11.

  A first cam cylinder 30 is disposed outside the fixed cylinder 20, and a zoom operation ring 40 is disposed outside the first cam cylinder 30. A first rectilinear cylinder 50 is disposed inside the fixed cylinder 20. The zoom operation ring 40 and the first cam cylinder 30 are coupled, and the rotational movement of the zoom operation ring 40 is transmitted to the first cam cylinder 30. The first cam barrel 30 is formed with a first rectilinear barrel cam groove 31 extending obliquely with respect to the optical axis direction on the peripheral surface. Further, a first rectilinear cylinder rectilinear guide groove 21 extending in the optical axis direction is formed on the peripheral surface of the fixed cylinder 20. On the outer peripheral surface of the first rectilinear cylinder 50, a rectilinear cylinder interlocking piece 51 that is engaged with the first rectilinear cylinder cam groove 31 of the first cam cylinder 30 and the first rectilinear cylinder rectilinear guide groove 21 of the fixed cylinder 20 is implanted. Has been. Thus, when the first cam cylinder 30 rotates with respect to the fixed cylinder 20, the first rectilinear cylinder 50 moves in the optical axis direction without rotating with respect to the fixed cylinder.

As shown in FIGS. 1 to 5, the first rectilinear cylinder 50 includes a front part 50A on the objective side, an intermediate part 50B having an inner diameter smaller than that of the front part 50A, and a rear part 50C having an inner diameter smaller than that of the intermediate part 50B. Have. As shown in FIG. 5, the rear portion 50C is formed as a protrusion protruding from the intermediate portion 50B toward the eyepiece side, and a through hole 50E is formed in the rear portion 50C. Further, as shown in FIG. 5, a screw hole 50 </ b> D for planting the straight cylinder interlocking piece 51 is formed in the intermediate portion 50 </ b> B.
A second rectilinear cylinder 60 is disposed inside the front portion 50 </ b> A of the first rectilinear cylinder 50. A second cam cylinder 70 is disposed inside the second rectilinear cylinder 60 and inside the intermediate portion 50 </ b> B of the first rectilinear cylinder 50. A first guide cylinder 80 is disposed inside the second cam cylinder 70 and inside the rear portion 50 </ b> C of the first rectilinear cylinder 50. Furthermore, a third lens group holding cylinder 100 is disposed inside the first guide cylinder 80. The rear end portion of the first guide tube 80, the rear portion 50C of the first rectilinear tube 50, and the front portion of the third lens group holding tube 100 are through holes in which a fixed piece 82 is formed in the rear portion 50C of the rectilinear tube 50. The fixed piece 82 is integrally fixed in a state of penetrating 50E. For this reason, the first guide cylinder 80 and the third lens group holding cylinder 100 are connected to the rear portion 50C of the first rectilinear cylinder 50, and together with the first rectilinear cylinder 50, the optical axis is not rotated. Move in the direction.

  The first cam cylinder 30 is formed with an interlocking lever rectilinear guide groove 32 extending in the optical axis direction. Further, the fixed cylinder 20 is formed with an interlocking lever ridge 22 that is inclined in the optical axis direction along the peripheral surface. Further, a notch 52 extending in the circumferential direction over a predetermined angular range is formed at the rear end portion of the first rectilinear cylinder 50. In addition, an interlocking lever 110 is provided that is slidable in the circumferential direction along a notch 52 formed at the rear end of the first rectilinear cylinder 50. A transmission piece 111 is implanted in the interlocking lever 110, and the transmission piece 111 is engaged with an interlocking lever rectilinear guide groove 32 formed in the first cam cylinder 30 and extending in the optical axis direction. As a result, when the first cam cylinder 30 rotates, the interlocking lever 110 moves forward together with the first rectilinear cylinder 50 and rotates in conjunction with the rotation of the first cam cylinder 30.

  The rear end of the second cam cylinder 70 is connected to the interlocking lever 110. The second cam cylinder 70 is formed with a second rectilinear cylinder cam groove 71 inclined in the optical axis direction along the circumferential surface. Further, the first guide cylinder 80 is formed with a second rectilinear cylinder rectilinear guide groove 81 extending in the optical axis direction. A second rectilinear cylinder interlocking piece 61 is planted on the inner surface of the second rectilinear cylinder 60, and the second rectilinear cylinder interlocking piece 61 includes the second rectilinear cylinder cam groove 71 of the second cam cylinder 70, and the first The guide cylinder 80 is engaged with the second rectilinear cylinder rectilinear guide groove 81. When the first cam cylinder 30 rotates, the second cam cylinder 70 rotates in conjunction with the first cam cylinder 30. Since the first guide cylinder 80 does not rotate with respect to the fixed cylinder 20, the second rectilinear cylinder 60 moves in the optical axis direction with respect to the first guide cylinder 80 by the rotation of the second cam cylinder 70. .

  A mechanism for moving the first rectilinear cylinder 50 and the second rectilinear cylinder 60 disposed in the fixed cylinder 20, that is, the first rectilinear cylinder 50, the second rectilinear cylinder 60, and the second cam cylinder 70. The first guide cylinder 80 is referred to as a feeding mechanism.

  A third cam cylinder 90 is disposed inside the first guide cylinder 80. The rear end portion of the third cam cylinder 90 is fixed to the interlocking lever 110 via the transmission piece 91. Accordingly, when the first cam cylinder 30 rotates, the third cam cylinder 90 also rotates in conjunction with the rotation. A second lens group sliding frame 120 that holds the second lens group B is disposed inside the third cam cylinder 90. The third cam cylinder 90 is formed with a second lens group sliding frame cam groove 92 that is inclined in the optical axis direction along the circumferential surface. A second lens group sliding frame rectilinear guide groove 83 extending in the optical axis direction is formed on the peripheral surface of the first guide cylinder 80. A second lens group sliding frame interlocking frame 121 is planted on the outer periphery of the second lens group sliding frame 120. The second lens group sliding frame interlocking piece 121 is engaged with the second straight guide groove 83 of the first guide cylinder 80 and the second lens group sliding frame cam groove 92 of the third cam cylinder 90. doing. When the first cam cylinder 30 rotates, the third cam cylinder 90 rotates in conjunction with the first cam cylinder 30. Since the first guide cylinder 80 does not rotate relative to the fixed cylinder 20, the second lens group sliding frame 120 moves in the optical axis direction by the rotation of the third cam cylinder 90.

  As described above, the rear end portion of the first guide tube 80, the rear portion of the first rectilinear tube 50, and the front portion of the third lens group holding tube 100 are integrally fixed by the fixed frame 82. Furthermore, a fifth lens group holding frame 130 that holds the fifth lens group E is connected to the rear end of the third lens group holding cylinder 100. Further, a guide rail 131 extending in the optical axis direction is provided in the third lens group holding cylinder 100, and the fourth lens group frame 140 that holds the fourth lens group D extends along the guide rail 131 along the optical axis. It is held movably in the direction. With this configuration, the third lens group C, the fourth lens group D, and the fifth lens group E move in the optical axis direction in conjunction with the optical axis movement of the first rectilinear cylinder 50 and the third lens group holding cylinder 100. Moving.

  Further, the third lens group holding cylinder 100 is provided with an autofocus motor 132 that rotates in response to an external input. When the autofocus motor 132 rotates, the fourth lens group D together with the fourth lens group frame 140 moves along the guide rail 131 in the optical axis direction with respect to the third lens holding cylinder 100.

  The third lens group holding cylinder 100 is provided with a camera shake correction unit 150 that holds the shift lens group Cr. The camera shake correction unit 150 moves the shift lens group Cr in a direction orthogonal to the optical axis in accordance with an output from a gyro mechanism provided in the lens barrel 10.

  Further, a diaphragm mechanism 101 is provided on the objective side of the third lens group C of the third lens group holding cylinder 100. In the present embodiment, the front part 50A and the intermediate part 50B of the first rectilinear cylinder 50, the second rectilinear cylinder 60, the second cam cylinder 70, and the first guide cylinder 80, that is, the feeding mechanism, is the objective side of the aperture mechanism 101. Is provided. Further, as will be described later, the third to fifth lens groups C, D, and E are held in the third lens group holding cylinder 100, and the third lens group holding cylinder 100 corresponds to the first rectilinear cylinder 50. It is fixed to the rear part 50C. Therefore, a portion excluding the attachment portion (rear portion 50C) for connecting the third lens group holding cylinder 100 that holds the lens group behind the stop of the first straight moving cylinder 50, the second rectilinear cylinder 60, and the second cam. The cylinder 70 and the first guide cylinder 80 are provided closer to the objective side than the aperture mechanism 101.

  A sixth lens group holding frame 160 that holds the sixth lens group F is attached to the inside of the mount 11.

  A zoom interlocking ring 170 that is rotatable along the inner surface of the fixed cylinder 20 is disposed on the imaging side of the feeding mechanism in the fixed cylinder 20. A recess is formed in the rear edge of the first cam cylinder 30. The fixed cylinder 20 is formed with a circumferential groove 23 extending in the circumferential direction. A transmission piece 171 is implanted on the outer peripheral surface of the zoom interlocking ring 170, and the transmission piece 171 passes through the circumferential groove 23 and is fitted into a recess formed at the rear edge of the first cam cylinder 30. Yes. As a result, when the first cam cylinder 30 rotates, the zoom interlocking ring 170 rotates in conjunction with the transmission piece 171.

  A notch extending in the direction of the optical axis is formed in a portion on the image forming side of the feeding mechanism of the fixed cylinder 20, and a position detection sensor 24 is provided so as not to be notched. The position detection sensor 24 includes a sensor main body 24B extending in the optical axis direction and a protrusion 24A movable in the optical axis direction with respect to the sensor main body 24B, and detects the position of the protrusion 24A. The zoom interlocking ring 170 is formed with a guide groove 172 so as to incline in the optical axis direction along the peripheral surface. The protrusion 24 </ b> A of the position detection sensor 24 is engaged with the guide groove 172 of the zoom interlocking ring 170. Thus, when the zoom interlocking ring 170 rotates in conjunction with the first cam cylinder 30, the protrusion 24A of the position detection sensor 24 is guided by the guide groove 172 and moved in the optical axis direction. Thereby, the rotation angle of the zoom interlocking ring 170, that is, the rotation angle of the first cam cylinder 30 can be detected based on the position of the protrusion 24 </ b> A detected by the position detection sensor 24.

  The lens barrel 10 also includes a distance measuring device (not shown) for measuring the distance to the object to be photographed and a control device (not shown) for controlling the autofocus motor 132. The distance to the photographing object measured by the distance measuring device and the rotation angle of the first cam cylinder 30 detected by the position detection sensor 24 are input to the control device. Then, the control device drives the autofocus motor 132 based on the input distance to the photographing target and the rotation angle of the first cam cylinder 30.

Next, the zoom operation in the lens barrel 10 of this embodiment will be described.
The zoom operation can be performed by rotating the zoom operation ring 40. When the zoom operation ring 40 is rotated, the first cam cylinder 30 is rotated in conjunction therewith.

  When the first cam cylinder 30 rotates, the first rectilinear cylinder interlocking piece 51 planted in the first rectilinear cylinder 50 causes the first rectilinear cylinder cam groove 31 of the first cam cylinder 30 and the first rectilinear advance of the fixed cylinder 20. Since it is engaged with the cylinder rectilinear guide groove 21, the first rectilinear cylinder 50 moves in the optical axis direction. Since the first rectilinear cylinder 50, the first guide cylinder 80, and the third lens group holding cylinder 100 are integrally coupled, the first guide cylinder is interlocked with the movement of the first rectilinear cylinder 50 in the optical axis direction. 80 and the third lens group holding cylinder 100 also move in the optical axis direction without rotating. In this way, the third lens group C, the fourth lens group D, and the fifth lens group E move in the optical axis direction in conjunction with the rotation of the zoom operation ring 40.

  When the first cam cylinder 30 rotates, the transmission piece 111 implanted in the interlocking lever 110 is engaged with the interlocking lever rectilinear guide groove 32 formed in the first cam cylinder 30 and extending in the optical axis direction. Therefore, together with the first rectilinear cylinder 50, the interlocking lever 110 moves in the optical axis direction while rotating around the optical axis. The rotation and movement in the optical axis direction of the interlocking lever 110 are transmitted to the second cam cylinder 70 and the third cam cylinder 90.

  When the second cam cylinder 70 is rotated, the second rectilinear cylinder interlocking piece 61 planted on the inner surface of the second rectilinear cylinder 60 is replaced with the second rectilinear cylinder cam groove 71 of the second cam cylinder 70 and the first guide. Since the cylinder 80 is engaged with the second rectilinear cylinder rectilinear guide groove 81, the second rectilinear cylinder 60 moves in the optical axis direction with respect to the first guide cylinder 80. In this manner, the first lens group A moves in the optical axis direction in conjunction with the rotation of the zoom operation ring 40.

  Further, when the third cam cylinder 90 rotates, the second lens group sliding frame interlocking piece 121 planted in the second lens group sliding frame 120 is moved to the second rectilinear guide groove 83 of the first guide cylinder 80, In addition, since the second lens group sliding frame cam groove 92 of the third cam cylinder 90 is engaged, the second lens group sliding frame 120 moves in the optical axis direction with respect to the first guide cylinder 80. In this manner, the second lens group B moves in the optical axis direction in conjunction with the rotation of the zoom operation ring 40.

  The rotation of the first cam cylinder 30 is transmitted to the zoom interlocking ring 170 via the transmission piece 171. When the zoom interlocking ring 170 rotates, the protrusion 24A of the position detection sensor 24 is guided in the guide groove 172 formed in the zoom interlocking ring 170 and is moved in the optical axis direction. Thus, the rotation angle of the zoom interlocking ring 170, that is, the rotation angle of the first cam cylinder 30 is detected based on the position of the protrusion 24A detected by the position detection sensor 24.

Next, the focus operation in the lens barrel 10 of this embodiment will be described.
The distance to the object to be imaged measured by the distance measuring device (not shown) and the rotation angle of the first cam cylinder 30 detected by the position detection sensor 24 are input to the control device. Then, the control device drives the autofocus motor 132 so that an image is formed on the optical element built in the camera body based on the input distance to the photographing target and the rotation angle of the first cam cylinder 30.

  When the autofocus motor 132 is rotated, the fourth lens group D together with the fourth lens group frame 140 moves along the guide rail 131 in the optical axis direction with respect to the third lens holding cylinder 100. Thereby, autofocusing can be performed.

  In addition, the fourth lens group frame 140 can be moved manually by rotating a focus operation ring 180 provided on the outer periphery of the lens barrel 10 to move the optical axis of the fourth lens group frame 140. Such a manual focus mechanism is incorporated in a space formed in the outer peripheral portion of the rear fixed cylinder 20 in the lens barrel 10.

  According to the lens barrel 10 of the present embodiment, since the feeding mechanism is provided in front of the aperture mechanism 101, a space can be secured at the rear part of the lens barrel 10. Accordingly, the long position detection sensor 24 can be incorporated into the lens barrel 10 without increasing the diameter of the lens barrel 10.

  Further, the integrated first cam cylinder 30 and zoom operation ring 40 are directly provided on the outer periphery of the fixed cylinder 20. Thereby, a large space in the fixed cylinder 20 can be secured, and the feeding mechanism can be arranged in the fixed cylinder 20.

  Further, since the diameter of the fixed cylinder 20 gradually decreases toward the objective side, a space can be secured in the outer peripheral part of the eyepiece side of the lens barrel 10, and a mechanism such as a manual focus mechanism is provided in this part. It can be incorporated.

DESCRIPTION OF SYMBOLS 10 Lens barrel 11 Mount 20 Fixed cylinder 21 1st rectilinear cylinder rectilinear guide groove 22 Interlocking lever protrusion 23 Circumferential groove 24 Position detection sensor 30 1st cam cylinder 31 1st rectilinear cylinder cam groove 32 Interlocking lever rectilinear guide groove 40 Zoom operation ring 50 1st rectilinear cylinder 51 1st rectilinear cylinder interlocking piece 52 Notch 60 2nd rectilinear cylinder 61 2nd rectilinear cylinder interlocking piece 70 2nd cam cylinder 71 2nd rectilinear cylinder cam 80 1st guide cylinder 81 2nd rectilinear cylinder rectilinear guide groove 82 Fixed frame 83 Second lens group sliding frame straight guide groove 90 Third cam cylinder 91 Transmission frame 100 Third lens group holding cylinder 101 Aperture mechanism 110 Interlocking lever 111 Transmission frame 120 Second lens group sliding frame 121 Second lens Group sliding frame interlocking frame 130 Fifth lens group holding frame 131 Guide rail 132 Autofocus motor 140 Fourth lens group holding frame 150 Correction unit 160 sixth lens group holding frame 170 zoom interlocking rings 171 transmits frame 180 focus operation ring

Claims (4)

A zoom lens barrel comprising at least a first lens group movable in the optical axis direction, and at least one lens group disposed closer to the image forming side than the aperture mechanism and movable in the optical axis direction,
A fixed cylinder;
A zoom ring disposed outside the fixed cylinder;
A first cam cylinder that is integral with the zoom ring and rotates relative to the fixed cylinder;
Holding a first lens group, and a rectilinear cylinder disposed inside the fixed cylinder,
The rectilinear cylinder is movable in the optical axis direction by rotating the first cam cylinder with respect to the fixed cylinder,
A holding member for holding at least one lens group that is movable in the optical axis direction provided on the image forming side with respect to the aperture mechanism is connected to an attachment portion formed at the rear portion of the rectilinear cylinder,
The zoom lens barrel according to claim 1, wherein a portion of the rectilinear cylinder excluding the attachment portion is provided closer to the objective side than the diaphragm mechanism. The straight cylinder is
A first rectilinear cylinder disposed inside the fixed cylinder; and a second rectilinear cylinder disposed inside the first rectilinear cylinder;
The first rectilinear cylinder is movable in the optical axis direction when the first cam cylinder rotates with respect to the fixed cylinder,
The zoom lens barrel is disposed inside the second rectilinear barrel, moves in the optical axis direction together with the first rectilinear barrel, and rotates in conjunction with the first cam barrel. And a rectilinear guide cylinder that is arranged inside the second cam cylinder and moves in the optical axis direction together with the first rectilinear cylinder,
The second rectilinear cylinder moves in the optical axis direction with respect to the first rectilinear cylinder by rotating the second cam cylinder with respect to the rectilinear guide cylinder. The zoom lens barrel described in 1.   3. The zoom lens barrel according to claim 1, wherein the fixed cylinder is formed in a shape such that the diameter gradually decreases toward the imaging side in the optical axis direction. The zoom lens barrel includes a zoom interlocking ring that can rotate in conjunction with the first cam cylinder along the inner surface of the fixed cylinder;
A position sensor attached to the rear of the fixed cylinder,
The position sensor includes a sensor body extending in the optical axis direction, and a protrusion that is movable in the optical axis direction with respect to the sensor body.
4. The zoom lens mirror according to claim 1, wherein the protrusion moves in the optical axis direction relative to the sensor main body in conjunction with rotation of the zoom interlocking ring. 5. Tube.

Images